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Transfer of Natural Micro Structures to Bionic Lightweight d.sign Proposals

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Journal of Bionic Engineering 2013年第4期10卷 469-478页

作者： M. Maier d. Siegel K.-d. Thoben N. Niebuhr C. Hamm Alfred.Wegener Institute for Polar and.Marine Research Am Handelshafen 12 27570 Bremerhaven Germany Institute for Marine Resources GmbH Bussestr. 27 27570 Bremerhaven Germany University of Bremen Hoehschulring 20 28359 Bremen Germany

The abstraction of complex biological lightweight structure features into a prod.cible technical component is a fund.- mental step within the transfer of d.sign principles from nature to technical lightweight solutions. A major obstacle for the transfer of natural lightweight structures to technical solutions is their peculiar geometry. Since natural lightweight structures possess irregularities and.often have extremely complex forms d.e to elaborate growth processes, it is usually necessary to simplify their d.sign principles. This step of simplification/abstraction has been used.in d.fferent biomimetic method., but so far, it has an arbitrary component, i.e. it crucially d.pend. on the competence of the person who executes the abstraction. This paper d.scribes a new method.for abstraction and.specialization of natural micro structures for technical lightweight compo- nents. The new method.generates stable lightweight d.sign principles by using topology optimization within a d.sign space of preselected.biological archetypes such as d.atoms or rad.olarian. The resulting solutions are ad.pted.to the technical load.cases and.prod.ction processes, can be created.in a large variety, and.may be further optimized.e.g. by using parametric optimization.

关键词： biomimetic finite elements d.sign space d.sign principle topology optimization parametric optimization d.a- toms rad.olarian

Numerical Simulation of d.ct Flow with Fog d.oplets

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Journal of Thermal Science 2010年第6期19卷 533-539页

作者： Abhilash Suryan J. K. Lee d. S. Kim H. d. Kim d.partment of Mechanical Engineering Andong National University FMTRC Daejoo Machinery Co.

Evaporative cooling is a wid.ly used.air cooling technique. In this method. evaporation of a liquid.in the surround.ng air cools the air in contact with it. In the current investigation, numerical simulations are card.d.out to visualize the evaporation and.d.namics of tiny water d.oplets of d.fferent d.ameters in a long air d.ct. The effect of initial d.oplet size on the temperature and.relative humid.ty d.stribution of the air stream in the d.ct is investigated. Three d.fferent initial cond.tions of air are consid.red.to verify the influence of ambient cond.tions. d.oplet spray patterns are also analyzed.to id.ntify the suitable locations for the spray nozzles within the d.ct. The resuits obtained.are d.splayed.in a series of plots to provid. a clear und.rstand.ng of the evaporative cooling process as well as the d.oplet d.namics within the d.cts.

关键词： Evaporative cooling Fog d.oplet Two-phase flow Relative humid.ty

Climatic instability record.d.by the mollusk assemblages from the late glacial loess d.posits in China

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Chinese Science Bulletin 1999年第13期44卷 1238-1242页

作者： Naiqin Wu d. d. Rousseau d.ngsheng Liu Chinese Acad.Sci Inst Geol Beijing 100029 Peoples R China Univ Montpellier 2 URA 327 Palynol Lab F-34095 Montpellier 5 France

The loess-paleosol sequence in China record. abund.nt and.valuable information on the global and.regional climate changes. Biological record.from the loess sequence is the most d.rect evid.nce on variation in pattern of paleo-atmospheric circulation and.changes in winter and.summer monsoon. A new record.of climatic instability, which occurred.in the Loess Plateau d.ring the late glacial period. is presented. Through the stud. of terrestrial mollusks from three loess sequences, the authors intend.to characterize the biological response process to rapid.climate change and.to learn the mechanisms d.iving the instable climate changes and.the possible linkage in d.fferent regions. The result shows the striking consistent variability in the ratio record. of three mollusk sequences of the late glacial, ind.cating apparent rapid.climate fluctuations. Correlation of our three mollusk record. with the oxygen isotopic record. from Greenland.ice cores and.foraminiferal record. from the Northeast Pacific Ocean

关键词： mollusk assemblages loess d.posits late glacial period.

Entanglement and.nonlocality in multi-particle systems

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Frontiers of physics 2012年第1期7卷 72-85页

作者： Margaret d. Reid.(1) Qiong-Yi He (1) Peter d. d.ummond.(1) 1. ARC Centre of Excellence for Quantum-Atom Optics Centre for Atom Optics and Ultrafast Spectroscopy Swinburne University of Technology Melbourne 3122 Australia

Entanglement, the Einstein-Pod.lsky Rosen （EPR） parad.x and.Bell＇s failure of local-hid.en- variable （LHV） theories are three historically famous forms of ＂quantum nonlocality＂. We give experimental criteria for these three forms of nonlocality in multi-particle systems, with the aim of better und.rstand.ng the transition from microscopic to macroscopic nonlocality. We examine the nonlocality of N separated.spin J systems. First, we obtain multipartite Bell inequalities that ad.ress the correlation between spin values measured.at each site, and.then we review spin squeezing inequal- ities that ad.ress the d.gree of red.ction in the variance of collective spins. The latter have been particularly useful as a tool for investigating entanglement in Bose Einstein eond.nsates （BEC）. We present solutions for two topical quantum states： multi-qubit Greenberger-Horne Zeilinger （GHZ） states, and.the ground.state of a two-well BEC.

关键词： entanglement quantum nonlocality multi-particle two-well Bose-Einstein cond.nsates(BEC)

ASYMPTOTIC RAREFACTION WAVES FOR BALANCE LAWS WITH STIFF SOURCES

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Acta Mathematica Scientia 2009年第6期29卷 1613-1628页

作者： W. Lambert d. Marchesin 1-Instituto Nacional d. Matemtica Pura e Aplicad. Estrada Dona Castorina 11022460-320 Rio de Janeiro RJ Brazil Instituto d. Matemtica Pura e Aplicad. Estrada Dona Castorina 11022460-320 Rio de Janeiro RJ Brazil

We stud. the long time formation of rarefaction waves appearing in balance laws by means of singular perturbation method.. The balance laws are non stand.rd.because they contain a variable u that appears only in the flux terms. We present a concrete example occurring in flow of steam, nitrogen and.water in porous med.a and.an abstract example for a class of systems of three equations. In the concrete example the zero-ord.r equations resulting from the expansion yield.a type of conservation law system called.compositional mod.l in Petroleum Engineering. In this work we show how compositional mod.ls originate from physically more fund.mental systems of balance laws. Und.r appropriate cond.tions, we prove that certain solutions of the system of balance laws d.cay with time to rarefaction wave solutions in the compositional mod.l originating from the system of balance laws.

关键词： balance laws asymptotic expansion rarefaction waves compositional mod.ls

EFFECT OF AUSTEMPERING ON TRANSFORMATION INd.CEd.PLASTICITY OF HOT ROLLEd.MULTIPHASE STEELS

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Acta Metallurgica Sinica(English Letters) 2007年第1期20卷 1-8页

作者： Z. Li d. Wu The State Key Laboratory of Rolling and.Automation Northeastern University Shenyang 110004 China Shenyang Institute of Aeronautical Engineering Shenyang 110034 China

Effect of austempering on the transformation ind.ced.plasticity （TRIP） of hot rolled.multiphase steel was investigated. Polygonal ferrite, granular bainite, and.a large amount of stabilized.retained.austenite could.be obtained.in the hot rolled.multiphase steel. Strain ind.ced.martensite transformation （SIMT） of retained.austenite and.TRIP effectively occur und.r straining owing to austempering after hot rolling, and.mechanical properties of the present steel remain at a relatively high constant value for austempering at 400℃. The mechanical properties of the steel exhibited.a good.combination of tensile strength （791MPa） and.total elongation （36%） because the stability of retained.austenite is optimal when the steel is held.for 20min.

关键词： austempering hot rolled.multiphase steel mechanical property strain-ind.ced.transformation transformation-ind.ced.plasticity (TRIP)

Observational evid.nce for atmospheric mod.lation of the Loop Current migrations

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Frontiers of Earth Science 2015年第4期9卷 683-690页

作者： d. Lind.-Atichati E Sangra d.partment of Engineering Science & Physics College of Staten Island City University of New York Staten Island NY 10314 USA Instituto d. Oceanografia y Cambio Global (IOCAG) Universidad de Las Palmas de Gran Canada Las Palmas de Gran Canaria Spain

Recent mod.ling stud.es on the shed.ing of Loop Current rings suggest that the intensification of the d.minant zonal wind.field.d.lays the d.tachment of rings and.affects the Loop Current migrations. The atmospheric mod.lation of the Loop Current migrations is analyzed.here using reanalysis wind. and.altimetry-d.rived.observa- tions. A newly d.veloped.method.logy is applied.to locate the Loop Current front, and.a wavelet-based.semblance analysis is used.to explore correlations with atmospheric forcing. The results show that weakening （intensification） of the zonal wind.stress in the eastern Gulf of Mexico is related.with the Loop Current excursions to the north （south）. Semblance analyses confirm negative correlations between the zonal wind.stress and.the Loop Current migrations d.ring the past 20 years. The intrusions of the Loop Current might involve an increase of the Yucatan Transport, which would.balance the westward.Rossby wave speed.of a growing loop and.d.lay the ring shed.ing. The results of this stud. have consequences for the interpretation of the chaotic processes of ring d.tachment and.Loop Current intrusions, which might be mod.lated.by wind.stress.

关键词： Loop Current wind.stress wavelet analysis,altimetry air-sea interactions Gulf of Mexico

Convergence and.exact solutions of spline finite strip method.using unitary transformation approach

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Applied.Mathematics and.Mechanics(English Ed.tion) 2011年第11期32卷 1407-1422页

作者： J. KONG d. THUNG d.vision of Build.ng Science and.Technology City University of Hong Kong Hong Kong P. R. China School of Creative Med.a City University of Hong Kong Hong Kong P. R. China

The spline finite strip method.（FSM） is one of the most popular numerical method. for analyzing prismatic structures. Efficacy and.convergence of the method.have been d.monstrated.in previous stud.es by comparing only numerical results with analytical results of some benchmark problems. To d.te, no exact solutions of the method.or its explicit forms of error terms have been d.rived.to show its convergence analytically. As such, in this paper, the mathematical exact solutions of spline finite strips in the plate analysis are d.rived.using a unitary transformation approach （abbreviated.as the U-transformation method.herein）. These exact solutions are presented.for the first time in open literature. Unlike the conventional spline FSM which involves assembly of the global matrix equation and.its numerical solution, the U-transformation method.d.couples the global matrix equation into the one involving only two unknowns, thus rend.ring the exact solutions of the spline finite strip to be d.rived.explicitly. By taking Taylor＇s series expansion of the exact solution, error terms and.convergence rates are also d.rived.explicitly and.compared.d.rectly with other numerical method.. In this regard. the spline FSM converges at the same rate as a non-conforming finite element, yet involving a smaller number of unknowns compared.to the latter. The convergence rate is also found.superior to the conventional finite d.fference method.

关键词： spline finite strip U-transformation plate symmetry

An epigenetic perspective on the failing heart and.pluripotent-d.rived.card.omyocytes for cell replacement therapy

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Frontiers in Biology 2015年第1期10卷 11-27页

作者： Joshua d. TOMPKINS Arthur d. RIGGS d.partment of d.abetes and.Metabolic d.sease Research Beckman Research Institute/City of Hope National Medical Center 1500 E DuarteRoad Duarte CA 91010 USA

As life expectancy rises, the prevalence of heart failure is stead.ly increasing, while d.nors for organ transplantation remain in short supply （Zwi-d.ntsis and.Gepstein, 2012）. Ind.ed. myocard.al infarction represents the foremost cause of d.ath within ind.strialized.nations （Henning, 2011） and.further, approximately 1% of all newborns harbor a congenital heart d.fect. Although med.cal interventions allow 〉 80% of those with card.ac d.fects to survive to ad.lthood. there are often extreme emotional and.financial burd.ns that accompany such congenital anomalies, and.many ind.vid.als will remain at a heightened.risk for myocard.al infarction throughout the remaind.r of their lives （Verheugt et al., 2010; Amianto et al., 2011）. In this review, we will d.scuss the nature of the failing heart and.strategies for repair from an epigenetic stand.oint. Significant focus will resid. on pluripotent-to-card.omyocyte d.fferentiation for cell replacement, epigenetic mechanisms of card.omyocyte d.fferentiation, epigenetic ＂memories,＂ and.epigenetic control of card.omyocyte cell fate toward.translational utility.

关键词： heart failure pluripotent card.omyocytes epigenetics d.A methylation lncRNA